Spinal manipulation for asthma: A systematic review of randomised clinical trials

  • E. Ernst
    Correspondence
    Tel.: +44 1392 424989; fax: +44 1392 427562.
    Affiliations
    Complementary Medicine, Peninsula Medical School, Universities of Exeter & Plymouth, 25 Victoria Park Road,Exeter EX2 4NT, UK
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Open ArchivePublished:July 31, 2009DOI:https://doi.org/10.1016/j.rmed.2009.06.017

      Summary

      Some clinicians believe that spinal manipulation is an effective treatment for asthma. The aim of this systematic review was to critically evaluate the evidence for or against this claim. Four electronic databases were searched without language restrictions from their inceptions to September 2008. Bibliographies and departmental files were hand-searched. The methodological quality of all included studies was assessed with the Jadad score. Only randomised clinical trials of spinal manipulation as a treatment of asthma were included. Three studies met these criteria. All of them were of excellent methodological quality (Jadad score 5) and all used sham-manipulation as the control intervention. None of the studies showed that real manipulation was more effective than sham-manipulation in improving lung function or subjective symptoms. It is concluded that, according to the evidence of the most rigorous studies available to date, spinal manipulation is not an effective treatment for asthma.

      Keywords

      The notion that spinal manipulation is an effective treatment for asthma might seem far fetched to many experts, yet it is an idea which is actively promoted by some clinicians. The American Chiropractic Association,

      American Chiropractic Association. Available from: <www amerchiro org/content_css cfm?CID=63>; 2008.

      the British Chiropractic Association,

      British Chiropractic Association. Available from: <www chiropractic-uk co uk/gfx/uploads/textbox/Happy%20families pdf>; 2008.

      the Canadian Chiropractic Association, the Chiropractic Patients Association

      Chiropractic Patients Association. Available from: <www chiropatients org uk/what-is-chiropractic aspx>; 2008.

      and the International Chiropractors Association

      International Chiropractors Association (ICA). Available from: <www chiropractic org>; 2008.

      and the International Chiropractic Paediatric Association

      International Chiropractic Paediatric Association. Available from: <www.chiro.org/research/ABSTRACTS/Asthma.shtml>; 2008.

      all claim or imply that chiropractic is an effective symptomatic treatment for asthma. A Google search on “asthma/chiropractic” generated 1,570,000 hits (date: 16 Jan 2009) and the majority of them seem to promote this concept. Case reports
      • Garde R.
      Asthma and chiopractic.
      • Hunt J.
      Upper cervical chiropractic care of a pediatric patients with asthma: a case study.
      • Killinger L.Z.
      Chiropractic care in the treatment of asthma.
      • Peet J.B.
      Case study: eight year old female with chronic asthma.
      • Worrill N.
      Asthma: a descriptive case study.
      • Fedorchuck C.
      Correction of subluxation and reduction of dysponesis in a 7 year-old child suffering from chronic cough and asthma: a case report.
      • Green A.
      Chronic asthma and chiropractic spinal manipulation: a case study.
      case series
      • Graham R.L.
      • Pistolese P.A.
      An impairment rating analysis of asthmatic children under chiropractic care.
      • Nilssen N.
      • Christiansen B.
      Prognostic factors in bronchial asthma in chiropractic practice.
      • Cuthbert C.A.
      Multi-modal chiropractic treatment approach for asthma: a 10-patient retrospective case series.
      uncontrolled studies
      • Jamison J.R.
      Asthma in a chiropractic clinic.
      • Peet J.B.
      • Marko S.K.
      • Piekarczyk W.
      Chiropractic response in the pediatric patient with asthma: a pilot study.
      • Lines D.
      A holistic approach to the treatment of bronchial asthma in a chiropractic practice.
      and a non-randomised trial
      • Bockenhauer S.E.
      • Julliard K.N.
      • Lo K.S.
      • Huang E.
      • Sheth A.M.
      Quantifiable effects of osteopathic manipulative techniques on patients with chronic asthma.
      also seem to support this view.
      Chiropractors employ a range of therapeutic modalities but the hallmark therapy is spinal manipulation.
      • Ernst E.
      Chiropractic: a critical evaluation.
      DD Palmer, the founding father of chiropractic, believed that most diseases, including asthma, were caused by subluxations of the vertebrae: spinal manipulations, or “adjustments, have to correct these abnormalities”.
      • Ernst E.
      Chiropractic: a critical evaluation.
      “This is still a central tenet of chiropractic”.

      CPS Position Statement. Chiropractic care for children: controversies and issues. Available from: <www cps ca English/statements/CP/cp02-01 htm>; 2008 [accessed 28 July 2008].

      As currently no systematic review of this specific area exists, it seems desirable to evaluate the evidence from rigorous trials on this topic. This systematic review is aimed at summarizing and critically evaluating the data from randomised clinical trials (RCTs) of spinal manipulation as a treatment of asthma.

      Methods

      Electronic searches were carried out (September 2008) in the following databases: Amed, Embase, Medline (using the Ovid interface) and Cinahl (using the Ebsco interface). The search terms were constructed over two concepts: spinal manipulation and asthma. Our own, extensive departmental files, the bibliographies of review articles and other relevant publications were hand-searched. No language or time limitations were imposed. The abstracts of the articles thus located were screened in End Note to remove duplicates and irrelevant studies.
      To be considered for inclusion, a clinical trial had to be randomised, test the effectiveness of spinal manipulation, focus on human patients (of any age) with asthma and include clinical outcome (e.g. lung function, symptoms, medication usage). Any type of control intervention was admissible. Studies of chiropractic or osteopathic treatments not involving spinal manipulation were excluded, e.g., [
      • Guiney P.A.
      • Chou R.
      • Vianna A.
      • Lovenheim J.
      Effects of osteopathic manipulative treatment on pediatric patients with asthma: A randomized controlled trial.
      ]. Trials which failed to include clinical endpoints or which were not fully published (e.g. available as an abstract only) were also excluded e.g., [

      Ali S, Hayek R, Holland R, et al. Effect of chiropractic treatment on the endocrine and immune system in asthmatic patients. In: Proceedings of the 2002 international conference on spinal manipulationToronto, Canada; October 4–5, 2002.

      ].
      Key data of the included trials were extracted according to prespecified criteria (Table 1). Data extraction was performed by two independent reviewers. The methodological quality of all reviewed studies was estimated using the Jadad score.
      • Jadad A.R.
      • Moore R.A.
      • Carroll D.
      • Jenkinson C.
      • Reynolds D.J.
      • Gavaghan D.J.
      • et al.
      Assessing the quality of reports of randomized clinical trials: is blinding necessary?.
      Again, this was done by two independent reviewers. A meta-analytical approach was considered but was rejected because of the clinical heterogeneity of the primary studies.
      Table 1Key data from the included trials.
      First author (year)Condition treatedSample SizeExperimental treatment (therapist)Control treatmentTreatment schedulePrimary outcome measureStatistical analysisDrop out/withdrawalMain resultsJadad score
      Neilsen (1995)Chronic asthma31High-velocity, low-amplitude thrusts at site of segmental dysfunction (chiropractor)(Sham-manipulation rapid change of position of patient without direct manipulative thrust)Twice weekly treatments for 4 weeks; 2 week washout then crossed over to alternative treatment for 4 weeksLung function tests, symptom score, bronchodilator use, bronchial reactivityRepeated measures ANOVA, no sample size calculation2 (Text is unclear)No significant differences between groups or any measure
      Very confusing results section.
      5
      Balon (1998)Childhood asthma91Adjustments as judged to be optimal involving high-velocity, low-amplitude, directional push (chiropractor)Sham-manipulation (gentle palpation to the spine and distraction manoeuvre low-amplitude low velocity)Three times weekly for 4 weeks, then twice weekly for 4 weeks, then weekly for 8 weeksLung function tests, symptom score, bronchodilator use, peak expiratory flowAnalysis of covariance10+1 removed (did not seem to use β-agonist >3/week)No significant differences between groups5
      Bronfort (2001)Mild to moderate childhood asthma36High-velocity, low-amplitude thrust to dysfunctional joints of the spine (chiropractor)Sham-manipulation (light manual contact without thrusts)Twenty treatments during 3 monthsLung function tests, patient-rated symptoms, medication useNo inter-group comparisons were made2Only intra-group changes were reported5
      a Very confusing results section.

      Results

      The searches located 35 articles of which three met the inclusion criteria
      • Nielson N.H.
      • Bronfort G.
      • Bendix T.
      • Madsen F.
      • Weeke B.
      Chronic asthma and chiropractic spinal manipulation: a randomised clinical trial.
      • Balon J.
      • Aker P.D.
      • Crowther E.R.
      • Danielson C.
      • Cox P.G.
      • O'Shaughnessy D.
      A comparison of active and simulated chiropractic manipulation as adjunctive treatment for childhood asthma.
      • Bronfort G.
      • Evans R.L.
      • Kubic P.
      • Filken P.
      Chronic pediatric asthma and chiropractic spinal manipulation: a prospective clinical series and randomized clinical pilot study.
      (Fig. 1). All of these RCTs tested chiropractic (as opposed to osteopathic, for instance) spinal manipulation and were sham-controlled. The treatment periods ranged between one and three months. Lung function tests were used in all studies to assess the success of the interventions. The sample sizes varied between 31 and 91. The methodological quality of all RCTs was excellent (Table 1). The quality of reporting, however, was poor in one study.
      • Nielson N.H.
      • Bronfort G.
      • Bendix T.
      • Madsen F.
      • Weeke B.
      Chronic asthma and chiropractic spinal manipulation: a randomised clinical trial.
      Figure thumbnail gr1
      Figure 1Flow chart of excluded and included articles and studies.
      The findings were consistently negative. Nielsen et al.
      • Nielson N.H.
      • Bronfort G.
      • Bendix T.
      • Madsen F.
      • Weeke B.
      Chronic asthma and chiropractic spinal manipulation: a randomised clinical trial.
      and Balon et al.
      • Balon J.
      • Aker P.D.
      • Crowther E.R.
      • Danielson C.
      • Cox P.G.
      • O'Shaughnessy D.
      A comparison of active and simulated chiropractic manipulation as adjunctive treatment for childhood asthma.
      failed to demonstrate significant inter-group differences. Bronfort et al found “little or no change” when comparing pre-test with post-test lung function data and patient-rated symptoms. This study was aimed at determining the feasibility of a definitive trial and thus did not report inter-group differences “because of the high risk of committing type I and type II errors”.

      Discussion

      The results of this systematic review demonstrate that currently there are no data from rigorous RCTs to suggest that spinal manipulation is an effective treatment for asthma. On the contrary, all three RCTs show no significant benefit from spinal manipulation compared to sham-manipulation. This suggests that other types of studies (Table 2) have generated false positive results due to selection, expectation or other types of bias.
      Table 2Excluded reports of chiropractic spinal manipulation.
      First author (year)Study designOutcomeReference
      Jamison (1986)Uncontrolled studyOverall improvement
      • Jamison J.R.
      Asthma in a chiropractic clinic.
      Lines (1993)Uncontrolled studyOverall improvement
      • Lines D.
      A holistic approach to the treatment of bronchial asthma in a chiropractic practice.
      Garde (1994)Case reportSymptomatic improvement
      • Garde R.
      Asthma and chiopractic.
      Killinger (1995)Case reportSymptomatic improvement
      • Killinger L.Z.
      Chiropractic care in the treatment of asthma.
      Peet (1995)Uncontrolled studyOverall improvement
      • Peet J.B.
      • Marko S.K.
      • Piekarczyk W.
      Chiropractic response in the pediatric patient with asthma: a pilot study.
      Graham (1997)Case series (n=81)Mostly positive, boys responded better than girls.
      • Graham R.L.
      • Pistolese P.A.
      An impairment rating analysis of asthmatic children under chiropractic care.
      Peet (1997)Case reportSymptomatic improvement
      • Peet J.B.
      Case study: eight year old female with chronic asthma.
      Nilssen (1998)Case seriesMost patients improved
      • Nilssen N.
      • Christiansen B.
      Prognostic factors in bronchial asthma in chiropractic practice.
      Worrill (1998)Case reportImprovements of symptoms
      • Worrill N.
      Asthma: a descriptive case study.
      Hunt (2000)Case reportSymptomatic improvement
      • Hunt J.
      Upper cervical chiropractic care of a pediatric patients with asthma: a case study.
      Green (2001)Case studyObjective improvement during therapy
      • Green A.
      Chronic asthma and chiropractic spinal manipulation: a case study.
      Bockenhauer (2002)Non-randomised pilot studyIncreased respiratory thoracic excursions
      • Bockenhauer S.E.
      • Julliard K.N.
      • Lo K.S.
      • Huang E.
      • Sheth A.M.
      Quantifiable effects of osteopathic manipulative techniques on patients with chronic asthma.
      Fedorchuk (2007)Case reportResolution of symptoms
      • Fedorchuck C.
      Correction of subluxation and reduction of dysponesis in a 7 year-old child suffering from chronic cough and asthma: a case report.
      Cuthbert (2008)Retrospective case seriesMostly positive
      • Cuthbert C.A.
      Multi-modal chiropractic treatment approach for asthma: a 10-patient retrospective case series.
      These unanimously negative findings seem to contradict conclusions from other reviews on the subject. Hawk et al suggest that “evidence from controlled studies…supports chiropractic care as providing benefit to patients with asthma…”.
      • Hawk C.
      • Khorsan R.
      • Lisi A.J.
      • Ferrance R.J.
      • Evans M.W.
      Chiropractic care for nonmusculoskeletal conditions: a systematic review with implications for whole systems research.
      Citing the Bronfort pilot study,
      • Bronfort G.
      • Evans R.L.
      • Kubic P.
      • Filken P.
      Chronic pediatric asthma and chiropractic spinal manipulation: a prospective clinical series and randomized clinical pilot study.
      Kemper et al recently stated “few RCTs have demonstrated significant benefits of chiropractic practice among paediatric patients.
      • Kemper K.J.
      • Vohra S.
      • Walls R.
      The use of complementary and alternative medicine in pediatrics.
      A Cochrane review, on the other hand, concludes that “there is insufficient evidence to support the use of manual therapies for patients with asthma”.
      • Hondras M.A.
      • Linde K.
      • Jones A.P.
      Manual therapy for asthma.
      Part of the apparent contradictions could be due to the fact that Hawk et al.
      • Hawk C.
      • Khorsan R.
      • Lisi A.J.
      • Ferrance R.J.
      • Evans M.W.
      Chiropractic care for nonmusculoskeletal conditions: a systematic review with implications for whole systems research.
      reviewed not just spinal manipulation but “chiropractic care”, i.e. the entire package of treatments administered by chiropractors. Similarly the Cochrane review
      • Hondras M.A.
      • Linde K.
      • Jones A.P.
      Manual therapy for asthma.
      is not focussed on spinal manipulation but on any type of manual therapy, including massage therapy.
      Therapeutic decisions are rarely made on the basis of therapeutic effectiveness alone. In the case of spinal manipulation, both safety and cost might come into play. Spinal manipulation has been associated with frequent but mild adverse effects
      • Ernst E.
      Prospective investigations into the safety of spinal manipulation.
      and (probably) infrequent but serious complications such as vertebral artery dissection.
      • Stevinson C.
      • Ernst E.
      Risks associated with spinal manipulation.
      The costs of any practitioner-based therapy that requires regular treatment sessions are bound to be considerable. Spinal manipulations are no exception.
      • White A.
      • Resch K.L.
      • Ernst E.
      A survey of complementary practitioners' fees, practice, and attitude to working within the national health service.
      Both factors would contribute to a recommendation against the use of spinal manipulation for the treatment of asthma.
      The question arises when one should consider a treatment to be of proven ineffectiveness. Science in general and the RCT in particular are not good tools for proving a negative. Proponents of spinal manipulation might therefore argue that, for a range of reasons, spinal manipulation is effective but the few RCTs available to date were inadequate and thus failed to demonstrate this fact. Even if this interpretation were correct, it would clearly be the responsibility of those who claim spinal manipulation to be effective to demonstrate this beyond reasonable doubt. In the absence of such proof, any claim that spinal manipulation (or indeed any other therapy) is effective seems unjustified and irresponsible.
      This review has several limitations. Even though the search strategy was thorough, there never can be an absolute certainty that all relevant studies were located. We know that journals of complementary and alternative medicine hardly ever publish negative results.
      • Ernst E.
      • Pittler M.H.
      Alternative therapy bias.
      If this publication bias pertains to the current subject as well, the true overall result might even be more convincingly negative than the one generated here. The paucity of studies included in this review is another serious drawback. Any conclusion drawn from such a body of evidence has to be tentative and might rapidly change if new evidence emerges.
      Systematic reviews often conclude that “more evidence is needed”. In this particular instance, however, I am not convinced that more studies of spinal manipulation should be funded with public money. The current evidence is clearly not positive, not even encouraging. If clinicians or organisations nevertheless imply (as they do) that spinal manipulation is an effective therapy for asthma, the onus is on them to fund, conduct and publish rigorous trials that demonstrate this claim to be true. Such trials should be designed along the lines of the best study that already exists.
      • Balon J.
      • Aker P.D.
      • Crowther E.R.
      • Danielson C.
      • Cox P.G.
      • O'Shaughnessy D.
      A comparison of active and simulated chiropractic manipulation as adjunctive treatment for childhood asthma.
      In particular they should minimize bias (e.g. by randomisation, adequate control intervention, sufficient sample size), make sure that spinal manipulation is administered optimally (e.g. by employing several well-trained therapists) and the outcome is measured adequately (e.g. relevant clinical endpoints, validated outcome measures).
      In conclusion, the currently available data from RCTs of spinal manipulation unanimously demonstrate that this treatment is not effective in alleviating the symptoms or signs of asthma.

      Conflict of interest

      Author “Edzard Ernst” has no conflicts of interest to declare.

      Acknowledgements

      I am indebted to Kate Boddy for conducting the literature searches and to Katherine Hunt for help with data extraction and evaluation.

      References

      1. American Chiropractic Association. Available from: <www amerchiro org/content_css cfm?CID=63>; 2008.

      2. British Chiropractic Association. Available from: <www chiropractic-uk co uk/gfx/uploads/textbox/Happy%20families pdf>; 2008.

      3. Canadian Chiropractic Association. Available from: <www ccachiro org/client/cca/ccansf/web/13257CF79D92197B85256D0300584B47?OpenDocument>; 2008.

      4. Chiropractic Patients Association. Available from: <www chiropatients org uk/what-is-chiropractic aspx>; 2008.

      5. International Chiropractors Association (ICA). Available from: <www chiropractic org>; 2008.

      6. International Chiropractic Paediatric Association. Available from: <www.chiro.org/research/ABSTRACTS/Asthma.shtml>; 2008.

        • Garde R.
        Asthma and chiopractic.
        Chiropr Pediatr. 1994; 1: 9-16
        • Hunt J.
        Upper cervical chiropractic care of a pediatric patients with asthma: a case study.
        J Clin Chiropr Ped. 2000; 1: 3-9
        • Killinger L.Z.
        Chiropractic care in the treatment of asthma.
        Palmer J Res. 1995; 2: 74-77
        • Peet J.B.
        Case study: eight year old female with chronic asthma.
        Chiropr Pediatr. 1997; 3: 9-12
        • Worrill N.
        Asthma: a descriptive case study.
        Br J Chiropr. 1998; 1: 4-5
        • Fedorchuck C.
        Correction of subluxation and reduction of dysponesis in a 7 year-old child suffering from chronic cough and asthma: a case report.
        J Vertebral Subluxation Res. 2007; Nov: 1-5
        • Green A.
        Chronic asthma and chiropractic spinal manipulation: a case study.
        Br J Chiropr. 2000; 4: 32-35
        • Graham R.L.
        • Pistolese P.A.
        An impairment rating analysis of asthmatic children under chiropractic care.
        J Vertebral Subluxation Res. 1997; 1: 41-48
        • Nilssen N.
        • Christiansen B.
        Prognostic factors in bronchial asthma in chiropractic practice.
        J Aust Chropr Assoc. 1998; 18: 85-87
        • Cuthbert C.A.
        Multi-modal chiropractic treatment approach for asthma: a 10-patient retrospective case series.
        Chiropr J Aust. 2007; 37: 19-24
        • Jamison J.R.
        Asthma in a chiropractic clinic.
        J Aust Chiropractors Assoc. 1986; 16: 137-143
        • Peet J.B.
        • Marko S.K.
        • Piekarczyk W.
        Chiropractic response in the pediatric patient with asthma: a pilot study.
        Chiropr Pediatr. 1995; 1: 9-13
        • Lines D.
        A holistic approach to the treatment of bronchial asthma in a chiropractic practice.
        Chiropr J Aust. 1993; 23: 408
        • Bockenhauer S.E.
        • Julliard K.N.
        • Lo K.S.
        • Huang E.
        • Sheth A.M.
        Quantifiable effects of osteopathic manipulative techniques on patients with chronic asthma.
        JAOA. 2002; 102: 371-375
        • Ernst E.
        Chiropractic: a critical evaluation.
        J Pain Sympt Man. 2008; 35: 544-562
      7. CPS Position Statement. Chiropractic care for children: controversies and issues. Available from: <www cps ca English/statements/CP/cp02-01 htm>; 2008 [accessed 28 July 2008].

        • Guiney P.A.
        • Chou R.
        • Vianna A.
        • Lovenheim J.
        Effects of osteopathic manipulative treatment on pediatric patients with asthma: A randomized controlled trial.
        J Am Osteopath Assoc. 2005; 105: 7-12
      8. Ali S, Hayek R, Holland R, et al. Effect of chiropractic treatment on the endocrine and immune system in asthmatic patients. In: Proceedings of the 2002 international conference on spinal manipulationToronto, Canada; October 4–5, 2002.

        • Jadad A.R.
        • Moore R.A.
        • Carroll D.
        • Jenkinson C.
        • Reynolds D.J.
        • Gavaghan D.J.
        • et al.
        Assessing the quality of reports of randomized clinical trials: is blinding necessary?.
        Contr Clin Trials. 1996; 17: 1-12
        • Nielson N.H.
        • Bronfort G.
        • Bendix T.
        • Madsen F.
        • Weeke B.
        Chronic asthma and chiropractic spinal manipulation: a randomised clinical trial.
        Clin Exp Allergy. 1995; 25: 80-88
        • Balon J.
        • Aker P.D.
        • Crowther E.R.
        • Danielson C.
        • Cox P.G.
        • O'Shaughnessy D.
        A comparison of active and simulated chiropractic manipulation as adjunctive treatment for childhood asthma.
        New Engl J Med. 1998; 339: 1013-1020
        • Bronfort G.
        • Evans R.L.
        • Kubic P.
        • Filken P.
        Chronic pediatric asthma and chiropractic spinal manipulation: a prospective clinical series and randomized clinical pilot study.
        J Man Phys Ther. 2001; 24: 369-377
        • Hawk C.
        • Khorsan R.
        • Lisi A.J.
        • Ferrance R.J.
        • Evans M.W.
        Chiropractic care for nonmusculoskeletal conditions: a systematic review with implications for whole systems research.
        J Alt and Comp Med. 2007; 13: 491-512
        • Kemper K.J.
        • Vohra S.
        • Walls R.
        The use of complementary and alternative medicine in pediatrics.
        Pediatrics. 2008; 122: 1374-1386
        • Hondras M.A.
        • Linde K.
        • Jones A.P.
        Manual therapy for asthma.
        The Cochrane Library. 2000; 1: 1-16
        • Ernst E.
        Prospective investigations into the safety of spinal manipulation.
        J Pain Sympt Manage. 2001; 21: 238-242
        • Stevinson C.
        • Ernst E.
        Risks associated with spinal manipulation.
        Am J Med. 2002; 112: 566-570
        • White A.
        • Resch K.L.
        • Ernst E.
        A survey of complementary practitioners' fees, practice, and attitude to working within the national health service.
        Complement Ther Med. 1997; 5: 210-214
        • Ernst E.
        • Pittler M.H.
        Alternative therapy bias.
        Complement Med. 1997; 385: 480